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Maintain cursor and screen position
This is for script writers who wish to save and restore the position of the normal cursor and its screen. To save cursor and screen positions: call CurPos("save") To restore positions: call CurPos("restore") Example: "Pressing shouldn't change a thing! try with special characters and such nmap :call Test() function Test() call CurPos("save") normal gg0 call CurPos("restore") endfunction function CurPos(action) if a:action "save" let b:saveve = &virtualedit let b:savesiso = &sidescrolloff set virtualedit=all set sidescrolloff=0 let b:curline = line(".") let b:curvcol = virtcol(".") let b:curwcol = wincol() normal! g0 let b:algvcol = virtcol(".") normal! M let b:midline = line(".") execute "normal! ".b:curline."G".b:curvcol."|" let &virtualedit = b:saveve let &sidescrolloff = b:savesiso elseif a:action "restore" let b:saveve = &virtualedit let b:savesiso = &sidescrolloff set virtualedit=all set sidescrolloff=0 execute "normal! ".b:midline."Gzz".b:curline."G0" let nw = wincol() - 1 if b:curvcol != b:curwcol - nw execute "normal! ".b:algvcol."|zs" let s = wincol() - nw - 1 if s != 0 execute "normal! ".s."zl" endif endif execute "normal! ".b:curvcol."|" let &virtualedit = b:saveve let &sidescrolloff = b:savesiso unlet b:saveve b:savesiso b:curline b:curvcol b:curwcol b:algvcol b:midline endif return "" endfunction Comments Benji Fisher's functions (foo.vim?) contain a Mark() function that returns an ex command that, when executed, restores the cursor and screen positions. An example: :let currPos = Mark() " Do some stuff :execute currPos I tested Benji's Mark() function and found that it doesn't hold the screen position well when the screen has already been scrolled past to the right - which is the original intention for retaining the screen position in the first place. Here's an example of how it breaks: fun TestMark() let a = Mark() "move to the start & end of the file to simulate cursor displacement normal gg0G0 exe a endfun nmap :call TestMark() Now try pressing at the end of a long line of a large file (try a binary file) that is longer than the window width. The cursor retains its position, but the screen position shifts. ---- cecutil.vim's SaveWinPosn() and RestoreWinPosn() functions do this too. ---- I tried cecutil's SaveWinPosn() and RestoreWinPosn() but it does not retain the screen's exact position once the cursor is at the end of a long line and the screen has been scrolled to the right. Perhaps it has to do with the 'scrolloff', 'sidescrolloff' & 'sidescroll' options. ---- The script above tries to restore the screen middle line number (so line xx will be at the middle screen before and after editing). This is not very reliable, because when the last line of the file is above the bottom of the screen, the cursor position after M is not in the middle of the screen. Save and restore the top of the screen (using H) is more reliable. So H "save line number x "do something "go to line number x zt should restore the screen better than the solution above. In the case where the last line of the file is below the bottom of the screen, then the two solutions are identical (except for the position of the cursor -- one in middle, one at top).